Humidifier drum construction

ABSTRACT

A humidifier drum construction having two spaced rigid circular end pieces and at least one unitary circumferentially disposed connecting piece therebetween, each connecting piece having an elongated flexible rail element and a plurality of rigid spaced rung elements thereon, whereby during drum fabrication the rail element can be flexed from the flat to a curvature smaller than the circular end pieces and the rung elements can be fitted transversely to and secured between the end pieces.

United States Patent [191 Knudsen Mar. 12, 1974 1 HUMIDIFIER DRUMCONSTRUCTION [75] Inventor: Robert F. Knudsen, Concord, Mich.

[73] Assignee: McGraw-Edison Company, Elgin,

[22] Filed: Sept. 7, 1972 [21] Appl. No.: 287,056

52 us. Cl 261/92, 55/400, 55/498, 1 55/500, 55/D1G. 31 51 rm. (:1 B01!3/04 [58] Field of Search 261/92; 55/400, 404, 497-499,

[56] References Cited UNITED STATES PATENTS 2,782,015 2/1957 Perrine261/92 X 2,941,620

V 6/1960 Thornburgh 55/498 3,596,886 8/1971 Trautman 261/92 3,598,3708/1971 Hoag 3,599,942 8/1971 Herr 261/92 Primary Examiner-Tim R. MilesAssistant Examiner-Richard L. Chiesa [57] ABSTRACT A humidifier drumconstruction having two spaced rigid circular end pieces and at leastone unitary circumferentially disposed connecting piece therebetween,each connecting piece having an elongated flexible rail element and aplurality of rigid spaced rung elements thereon, whereby during drumfabrication the rail element can be flexed from the flat to a curvaturesmaller than thecirculalr end pieces and the rung elements can be fittedtransversely to and secured between the end pieces.

8 Claims, 6 Drawing Figures HUMIDIFIER DRUM CONSTRUCTION In certainhumidifying devices, it is common to support a porus matting on acylinder drum, to rotate the drum through water to wet the matting, andto provide forced air flow through the wetted matting for addingmoisture to the air. The drum is formed of plastic to be I lightweightand corrosive resistant, and must be shaped true to allow proper supportin and rotation through the water.

An object of this invention is to provide a drum construction havingseparate prefabricated components that can be easily and accuratelyassembled to form the finished drum. This allows the components to befabricated, if required by a plastic specialist and shipped to thehumidifier manufacturer, who then can assemble and secure the componentstogether as required, using perhaps at most only simple fixtures orassembly aids.

Specifically, the invention discloses a humidifier drum having rigid endpieces either or each being provided with the-appropriate required closetolerance drum support edges, and further having at least one unitarypiece connected between the end pieces. Each unitary connecting piece isin the form of a ladder having at least one flexible elongated railelement and a plurality of spaced rigid rung elements thereon. The endand connecting pieces can be shipped flat or nested with like pieces,can be assembled such as in a fixture by flexing the rail element to thecurvature of the end pieces and fitting the rung elements between theend pieces, and can be secured together as by mechanical or chemicalbonding.

The invention will be more fully understood and appreciated afterreferring to the following specification, the accompanying drawingforming a part thereof, wherein:

FIG. I is a perspective view of a drum formed according to the inventiondisclosed herein, and showing in phantom its typical relationship in ahumidifier;

FIG. 2 is a longitudinal cross section of the assembled humidifier drumshown in FIG. 1;

FIG. 3 is a top plan view of a preferred embodiment of a connectingpiece used in the fabrication of the drum shown in FIGS. 1 and 2;

FIG. 4 is an elevational view of the connecting piece sembly; and

FIG. 6 is a sectional view similar to FIG. 2, except showing the end andconnecting pieces preassembled.

The humidifier drum assembly 10 shown is typically rotated about ahorizontal axis where the lower part of the drum lies beneath and passesthrough water confined in an open top tank within a humidifier case. Thedrum assembly consists of a structural drum fonn 12 which has an openperiphery and a porous matting 14 supported on the periphery whichbecomes wetted as the drum is rotated through the water. A fan 18(phantom only) draws ambient air through an opening 20 (phantom only) inthe case for forced air flow thereafter through the wetted matting anddischarge outside the humidifier.

The disclosed humidifier drum 12 has a pair of spaced end pieces 30 and32 and at least one unitary piece 34 connected between the end pieces.The end piece 30 is actually a hoop configuration and has a circularinner edge 36 which can ride on spaced powered rolls 37 (FIG/1 phantomonly) journaled from the humidifier case showing one typical drivesupport of the drum. The end piece 32 is shown as a closed disc havingconical wall 38 effective to diffuse the air coming toward it from thefan 18 to the circumferential drum periphery and matting 14 thereon. Thewall 38 is well drafted even to its outer edge to allow compact nestingof line end pieces 32 within one another. The end pieces 30 and 32 havecircular radially extended rims 40 and 42 respectively, typically ofequal size where the drum is to be a right angle cylinder, and mutuallyfacing cylindrical bosses 44 and 46 likewise of the same size.

The connecting piece 34 is fabricated as by molding from plastic as aunitary component having a pair of elongated side rails 48 and 50 and aplurality of spaced cross or rung elements 52 connected between therails. The rails are of rectangular cross section narrow in thedirection transverse to the rungs to allow the flexure from the flat(FIG. 4) to the circular (FIG. 5) and wide in a direction parallel tothe rungs to give lateral stability to the piece. Each rung is circularor eliptical in cross section to provide smooth exterior surfaces andgive lateral rigidity.

In the configuration shown, open recesses 54 and 56 are provided in theend piece bosses to receive rail elements 48 and 50 respectively, of theconnecting element 34. To assemble the components, side rail 50 isfitted into its receiving recess 56 and the opposite end piece 30 isfitted with its recess 54 over the opposite side rail 48. The componentsare then fused in place by adhesive or by chemical bonding, or byultrasonic welding or by staking. To provide for a foolproof as sembly,the eliptical cross section of the end rungs is extended across the railand the end piece recesses are enlarged in only the correspondingspecific areas to receive these rungs. When assembled, the outercircumferential land areas 60 and 62 of the end piece bosses and thecentral part of each rung generally line up with one another so that thematting 14 can be uniformly supported thereon between the rims 40 and42.

While end piece 30 is shown with an interior edge that rides on thedrive rollers, it would be entirely possible for the humidifier case tohave support rolls (not shown) upon which the end piece exterior edges40 and/or 42 would ride for powered support of the drum. Likewise, thediffuser end piece 32 is shown completely closed in the center, but thiscould be modifiedby having an opening covered by matting if greatermatting surface area were desired. Likewise the connecting element 34has been illustrated as having two side rails, although a third railmight be added for rigidity, or the elongated rail might actually belocated spaced from the rung ends which thus would be directly securedto the end pieces. Only a single connecting element 34 has beenillustrated which curves almost throughout the 360 of the circle withthe end rungs 52 spaced apart only some 5 to 15 consistent withmanufacturing toler ances without causing binding of same. It would bepossible for extremely large drums where the length of a singleconnecting element might be too cumbersome to handle to use more thanone such connecting element. In such a case, each of perhaps two similarelements would extend less than 180 again allowing an appropriate amountof clearance between the adjacent ends.

What is claimed is:

l. A humidifier drum, comprising in combination a pair of end pieces andinnerconnecting means between and fixedly locating said end pieces, eachend piece being rigid and having similarly sized circular exterioredges, one of the end pieces being in the form of a hoop and therebyalso having an interior edge, the innerconnecting means consisting of atleast one unitary piece having at least one elongated rail element and aplurality of spaced cross rung elements thereon, the rail element beingflexible in the direction transverse to the rung elements to allow theshaping of same from the flat to a curve smaller than the exterior edgesof the end pieces and the rung elements each being rigid and terminatingat their ends along spaced parallel planes, and means between the endpieces'and each unitary piece for rigidly joining the pieces togetherwith each rail element extending parallel of and the rung elementsextending transversely of the end piece exterior edges.

2. A humidifier drum according to claim 1, wherein each unitary piecehas a pair of elongated rail elements and the spaced cross rung elementsare extended transversely of and between the rail elements.

3. A humidifier drum according to claim 1, wherein each end piece has anannular boss disposed to project toward the other in assembled positionand being of similar size and shape, and wherein each unitary piececooperates with the end piece bosses effective for joining the piecestogether.

4. A humidifier drum according to claim 3, wherein each boss is providedwith a recess suitable for receiving and cooperating with the unitarypiece effective for rigidly joining the pieces together.

5. A humidifier drum according to claim 3, wherein each unitary piecehas two elongated rail elements and the cross rung elements are extendedtransversely of and between and terminate at the rail elements andwherein the end piece bosses have annular recesses provided in adjacentfaces thereof suited to receive the rail elements effective for joiningthe pieces together.

6. A humidifier drum according to claim 5, wherein each rung element hasa generally circular or eliptical cross section to provide a smoothexterior surface devoid of corners.

7. A humidifier drum according to claim 5, wherein each end piece has acircumferential land area and a radial rim outwardly adjacent the landarea, and wherein the exterior edge of each rung element lines up withthe adjacent end piece land areas.

8. A humidifier drum, comprising in combination a pair of end pieces andinnerconnecting means between and fixedly locating said end pieces, eachend piece being rigid and having exterior edges sized to define theexterior of the drum, the innerconnecting means consisting of at leastone unitary piece having a pair of elongated rail elements and aplurality of spaced cross rung elements extended therebetween, the railelements being flexible in the direction transverse to the rung elementsto allow the shaping of same from the flat to a curve smaller than theexterior edges of the end pieces and the rung elements each being rigid,and means between the end pieces and rail elements of each unitary piecefor rigidly joining the pieces together with each rail element extendingparallel to and the rung elements extending transversely of the endpiece exterior edges.

1. A humidifier drum, comprising in combination a pair of end pieces andinnerconnecting means between and fixedly locating said end pieces, eachend piece beinG rigid and having similarly sized circular exterioredges, one of the end pieces being in the form of a hoop and therebyalso having an interior edge, the innerconnecting means consisting of atleast one unitary piece having at least one elongated rail element and aplurality of spaced cross rung elements thereon, the rail element beingflexible in the direction transverse to the rung elements to allow theshaping of same from the flat to a curve smaller than the exterior edgesof the end pieces and the rung elements each being rigid and terminatingat their ends along spaced parallel planes, and means between the endpieces and each unitary piece for rigidly joining the pieces togetherwith each rail element extending parallel of and the rung elementsextending transversely of the end piece exterior edges.
 2. A humidifierdrum according to claim 1, wherein each unitary piece has a pair ofelongated rail elements and the spaced cross rung elements are extendedtransversely of and between the rail elements.
 3. A humidifier drumaccording to claim 1, wherein each end piece has an annular bossdisposed to project toward the other in assembled position and being ofsimilar size and shape, and wherein each unitary piece cooperates withthe end piece bosses effective for joining the pieces together.
 4. Ahumidifier drum according to claim 3, wherein each boss is provided witha recess suitable for receiving and cooperating with the unitary pieceeffective for rigidly joining the pieces together.
 5. A humidifier drumaccording to claim 3, wherein each unitary piece has two elongated railelements and the cross rung elements are extended transversely of andbetween and terminate at the rail elements and wherein the end piecebosses have annular recesses provided in adjacent faces thereof suitedto receive the rail elements effective for joining the pieces together.6. A humidifier drum according to claim 5, wherein each rung element hasa generally circular or eliptical cross section to provide a smoothexterior surface devoid of corners.
 7. A humidifier drum according toclaim 5, wherein each end piece has a circumferential land area and aradial rim outwardly adjacent the land area, and wherein the exterioredge of each rung element lines up with the adjacent end piece landareas.
 8. A humidifier drum, comprising in combination a pair of endpieces and innerconnecting means between and fixedly locating said endpieces, each end piece being rigid and having exterior edges sized todefine the exterior of the drum, the innerconnecting means consisting ofat least one unitary piece having a pair of elongated rail elements anda plurality of spaced cross rung elements extended therebetween, therail elements being flexible in the direction transverse to the rungelements to allow the shaping of same from the flat to a curve smallerthan the exterior edges of the end pieces and the rung elements eachbeing rigid, and means between the end pieces and rail elements of eachunitary piece for rigidly joining the pieces together with each railelement extending parallel to and the rung elements extendingtransversely of the end piece exterior edges.